# Author:sp
# CreaTime: $(DATE)
# FileName: $(NAME)
# Description: simple introdution of the code
import math
class Circle():
    def __init__(self,r):
        self.r=r
    def get_area(self):
        return math.pi*math.pow(r,2)
    def get_perrmeter(self):
        return 2*math.pi*r
if __name__=='__main__':
    r=int(input('请输入你的半径'))
    c=Circle(r)
    print(f'⚪的面积为{c.get_area()}')
    print(f'⚪的周长为{c.get_perrmeter()}')
    print('圆的面积为{:.2f}'.format(c.get_area()))
    print('圆的周长为{:.2f}'.format(c.get_perrmeter()))